Conventionally, fractures or damages on tooth roots or bones, when occurred, are cured by implanting the implants such as artificial tooth roots or artificial bones.
For conventional tooth roots, there have been known ones formed of titanium metal and shaped as screws as to be physically secured onto jawbones. Please see, for example, JP-07(1995)-313529A (Japanese Unexamined Patent Publication H7-313529). Ones modified as follows from the above have been also known, a hydroxyapatite layer is formed on the titanium metal by a plasma vapor deposition technique, where the hydroxyapatite layer is highly compatible with the bones and facilitates conglutination with the jawbones. Please see, for example, Biomaterials 23(2002) 2569-2575, and Journal of Materials Processing Technology 65(1997) 73-79.
Whereas a natural tooth has a periodontal membrane that acts as a shock absorber, the artificial tooth of the conventional technique does not have such shock-absorbing element. Thus, dental articulation pressure is directly transmitted onto the jawbone as to hamper mechanical balance with other teeth. This may eventually cause bone resorption and thereby flailing or moving of the artificial tooth root and thus might cause serious conditions of sickness and injury by bacterial infection or the like.
Moreover, the conventional ones having a hydroxyapatite layer have a low crystallinity in respect of the hydroxyapatite and have low adhesion strength at interface with the titanium metal. Thus, dissolving away or detachment of the layer might occur so that the artificial tooth root would not be secured on the jawbone.
Hence, it is to provide an implant that is able to be strongly secured in a living body as well as a manufacturing method of such implant.